I’m a senior in high school, and the time is fast approaching where I need to start putting together my applications. However, I don’t know who I can ask for a letter of recommendation, which is a requirement for most of the schools I wanna apply to. Junior year was completely on Zoom, so I didn’t get a chance to develop any real relationships with my teachers. One of them said I stood out to her in class, and I asked her and another teacher for NHS recommendations, which they gave me, but I feel like they don’t know me well enough to write a college letter of rec. And freshman and sophomore year I was shy and barely talked in any of my classes. Now I feel like I’m screwed. I’m a good student, but I can’t imagine any of my old teachers would have a whole lot else to say about me. It’s stressing me out 
You seemed to solve your own problem. Move on and write an an amazing essay. Maybe ask if they are willing to review it with you.
“move on” as in just don’t ask anyone for a letter? or ask the teachers that i mentioned?
Lol… Ask the teachers that you identified.
You need to ask - the teachers can not the type of person they perceive you to be even though they don’t know you well. This is common. Alternatively, you can limit yourself to schools that don’t require recommendations but it doesn’t seem like you want to go that route. There’s many, by the way.
But I’m sure if you ask a few, you’ll get it done.
You can also apply RD and really make an impression with a few of your teachers this fall. Then ask them to write you a rec. (That is my son’s plan and it seems to be working okay so far…)
You can ask the teachers who recommended for NHS and give them a brag sheet/high school resume/cheat sheet. I think that is pretty commonly done. It just helps jog their memories and fills in any gaps.
Just chiming in to say you are not alone! So many schools were all-remote in the last year and a half. I just finished watching the webinar from my son’s high school, and the counselors specifically say it’s fine to ask your junior year remote teachers for LORs. Although it feels strange, every student is in the same boat and teachers are ready to handle writing letters for students they never met in person. It’s ok! 
There will be a lot of bland letters of recommendation being submitted this year, because most students are in the same situation. It’s just where the world is at now. If a teacher told you that you stood out, you are probably in better shape for LORs than most.
A lot of people will be in a similar situation. I’d ask the two teachers you asked for NHS. When you talk to them say you recognize that writing a letter of recommendation may be difficult with remote learning last year and ask if there is anything you can provide them to help personalize their letters (ex. a resume, a list of activities, some accomplishments in their class etc.).
And as an aside, I’d ask the teachers as soon as school starts. At least in our district many students line up their teacher letter of recommendations by the end of junior year.
My kid’s high school has students fill out an information sheet to give to their teachers when they ask for a letter of recommendation. This helps the teacher remember what they did in their class and also opens the door for them to ask questions about other things on the information sheet that may help them write a more informed letter.
It sounds like your high school doesn’t expect this. However, you can write an email requesting the letter that includes information about what you learned in their class, how you’ve used what you learned in the class more recently, and anything else about yourself that would help a teacher write your recommendation.